Police hunting the so-called Croydon Cat Killer appear to now be favouring the theory that the pets are already dead when they come into contact with a human who they suspect is then mutilating the animals.

A number of lines of inquiry have been pursued throughout the investigation but it appears that the Met Police and SNARL, the animal rescue group which has been helping with the inquiry, now differ in their views on how the cats are dying.

Tony Jenkins and partner Boudicca Rising, who run South Norwood Animal Rescue and Liberty (SNARL), have been adamant that the cats are being killed by a human.

But a Met Police spokesman told the Advertiser this week: "With reference to [the] 'cat killer', the allegations are almost exclusively of mutilations of dead cats, not of cats being killed by a human."

This seems to be a deliberate change of direction from the force.

Back in 2016 Detective Sergeant Andy Collin had told the Advertiser he favoured the theory that a human was to blame.

He said: "Until I get firm evidence to suggest it is cars then I'm exploring that it could well be something else. We are leaning towards deliberate.

"There's not evidence to say they were deliberately killed. They appear to have been. But until we have got further evidence we can't really commit to definite but I can say they appear to be.

He said: “We are investigating a number of leads, and are keeping an open mind in terms of suspects, while following up different lines of enquiry.

“We are now convinced the cats are being killed and then mutilated.”

DS Collin is no longer involved in the investigation, having left Croydon.

And there have been suggestions that the Met has significantly reduced the resources it is putting into the investigation in recent months.

When asked by the Advertiser whether this is the case, the police spokesman said: "We’re not discussing numbers of officers – although it’s worth noting that few if any officers have ever worked full time on this, so it’s difficult to quantify."

The spokesman added: "Police are working with the RSPCA, Hertfordshire Constabulary and specialists in veterinary pathology and anthropology in order to review and further examine all information gathered during the course of the investigation.

"We expect to make a further announcement once we have concluded this work along with these specialists.

"There has been no arrest and enquiries continue."

Harley was found with his tail missing and a blunt force head injury (Image: Samantha Brown)

A recent piece in the Guardian reported that a team of 15 officers were investigating the case at one point but said Mr Jenkins understood that just two officers are now sharing one role.

Suggestions that the cats could have been killed by foxes or in car accidents have always been refuted by SNARL.